Will Water Flow in Syphon System?

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jackywacky
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Greetings, 1st timer here,

I have a question such as the follow :

If i have a syphon system (similar to that of a toilet cystern) , but the outlet pipe in which it is connected to the U-tube is filled with water, but has a little air pocket, in other words, (filled but not fully filled pipe). If i pull the diaphragm upwards, would the water flow?

Thanks.
 
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I am new to this too. I would guess the as long as the water in the tank portion has greater potential than that of the u-tube it will flow and push the air pocket out as well. The water in the tank should have a high enough volume and be located high enough above the u-tube for it to flow. Also assuming that the air pressure will be enough to overcome any pressure that may build up if the u-tube is sealed in a work producing system. Just guessing from what I know which is not a lot.
 
Bloc911, do you mean that for example, if my toilet bowl cystern is connected to a toilet bowl, but the pipe connecting both the siphon outlet and the toilet bowl is filled with water, if i pull the diaphragm upwards, the siphon will still start?
 
It will. You can think of the air as any fluid. It, like anything else, will exert a force on the next section of liquid proportional to the pressure.

However, when considering air and liquid, there is a significant buoyant force. So, if you did in fact have a "U"-shaped tube, the air pocket "could" rise up both sides and break the "seal" (for lack of a better word). Anyone who has siphoned knows that air pockets can ruin the flow.